I will be starting Geometry in the fall with my 10 yr old DS. He loves math and is excited about it. We will be using Right Start’s a Geometric Approach. However, I found this book and we have started reading it together to prepare him for Geometry and why we study it and how it has evolved, the uses for our time, etc. The book is titled The String, Straightedge and Shadow. We are only on Chapter 4, but are enjoying it so much. While I certainly am not qualified to judge if a book would be considered a living book, I think this one would be. It’s bringing to life for him (and me!) the history of why we study geometry and men have used it to improve their lives over the centuries!